This invention relates to a method and system for marking the inner surfaces of a firearm with an identifying indicia for transfer to the slug and casing of a bullet when it is fired, reading the indicia from the slug and/or casing and identifying the firearm therefrom and, in particular, to the modification of the inner surfaces of a firearm using a laser for the purpose of producing one or more areas of permanent grooves, which impart firearm data onto slugs passing through the barrel in contact with the inner surface of the barrel and onto casings in contact with the breech of the firearm to form a barcode-like pattern which may be read by a desktop or portable barcode scanner and matched to the firearm and analyzed to provide search data.
In order to link a bullet with the firearm that fired it, it is known in the art to examine a bullet, usually comparatively with another bullet, each with small, irregular microscopically viewable markings imparted during firing to determine a similarity between such markings whereby to support a conclusion that both bullets were fired from the same firearm.
In order to facilitate ballistic identification procedures with only the fired bullet available, various systems have been proposed in which bullets are marked by placing a channeled ring containing a number of dye bars in a groove in the barrel, which impart markings to the bullets which pass over them. The dye bars are assembled in different combinations according to a preset code which corresponds to the firearm""s serial number. Other systems have been proposed in which the identifying markings are an integral part of the barrel and bore surface so that they cannot be removed without damaging or disabling the firearm. Among the problems with such systems is that the identifying marking elements must be incorporated during manufacture of the firearm.
Use of a laser to etch the bore of a fire arm is disclosed in U.S. Pat. No. 6,462,302 to Grow discloses a device for etching the bore of a firearm and a scanner for reading the etchings from a slug of a bullet. The laser beam which etches the bore is directed onto a mirror in an etching tube which directs the beam to bore surface.
The laser etching system of the present invention includes a computer controlled laser system adapted to etch the bore and breach of a firearm using an etching probe inserted into the barrel of the firearm. Firearm identifying data, such as a serial number, are etched in both the bore and the breech of the firearm in the form of a barcode or other identifying indicia. Registration data corresponding to the owner of the firearm and the serial number or other firearm identifying data are entered into a computer and transferred to a central database. A slug fired from an etched firearm and the casing are marked with the etched barcode. A computer controlled scanning system reads the barcode and translates it into a serial number or other firearm identifying data for comparison with serial number stored in the central database.
Other advantages of the invention will become apparent from the following description taken in connection with the accompanying drawings, wherein is set forth by way of illustration and example, an embodiment of this invention.